A protester holds a placard reading "This is 2013, not 1984" during a demonstration against the National Security Agency (NSA) and in support of U.S. whistleblower Edward Snowden, July 27, 2013. Photo: Reuters

The National Security Agency, or NSA, on Friday, admitted to some instances over the last decade when its officials deliberately exceeded the NSA's surveillance authority.

"Very rare instances of willful violations of NSA's authorities have been found," the NSA said in a statement, according to the Associated Press.

The agency said those “instances” did not involve violations of the Foreign Intelligence Surveillance Act, or FISA, and those involved were disciplined.

The "NSA takes very seriously allegations of misconduct, and cooperates fully with any investigations -- responding as appropriate," the NSA statement said. "The NSA has zero tolerance for willful violations of the agency's authorities."

However, according to a Wall Street Journal report, the willful violations, which included cases where employees abused their power to spy on love interests, were not as rare as the NSA claims. Snooping on love interests was so prevalent, according to the report, employees gave the practice had a code name of its own.

According to the U.S. officials, who were quoted by the Journal, the NSA employees referred to the practice as LOVEINT -- a short label for collecting intelligence from lovers. A handful of such cases, which involved NSA workers using the agency’s tracking systems to spy on their love interests, were reported in the last decade.

Earlier this week, the NSA's inspector general's office had briefed the Senate Intelligence Committee on the willful violations.

"The committee has learned that in isolated cases over the past decade, a very small number of NSA personnel have violated NSA procedures -- in roughly one case per year," Sen. Dianne Feinstein, the California Democrat who chairs the committee, said in a statement Friday.

Feinstein added that in most of these cases, the spying did not take place in the U.S., and the committee is reviewing the incidents.

"I have been informed by the NSA that disciplinary action has been taken, and I am reviewing each of these incidents in detail," Feinstein added.

Last week, officials admitted the NSA had violated privacy rules on nearly 3,000 occasions over a one-year period, and a secret FISA court ruling from 2001 that was declassified this week showed the agency had collected about 56,000 emails from Americans illegally.